SERVER-47648 Simplify single node replset stepup on initiate and reconfig

(cherry picked from commit 49cc63fbb37f8a51f845c8d35bdb2f9c11219dab)

10 files changed, 126 insertions, 122 deletions

diff --git a/src/mongo/db/repl/replication_coordinator_impl.cpp b/src/mongo/db/repl/replication_coordinator_impl.cpp
index 9aaa120dcde..9fee5cc1f05 100644
--- a/src/mongo/db/repl/replication_coordinator_impl.cpp
+++ b/src/mongo/db/repl/replication_coordinator_impl.cpp
@@ -3835,12 +3835,6 @@ ReplicationCoordinatorImpl::_updateMemberStateFromTopologyCoordinator(WithLock l
     const MemberState newState = _topCoord->getMemberState();
 
     if (newState == _memberState) {
-        if (_topCoord->getRole() == TopologyCoordinator::Role::kCandidate) {
-            invariant(_rsConfig.getNumMembers() == 1 && _selfIndex == 0 &&
-                      _rsConfig.getMemberAt(0).isElectable());
-            // Start election in protocol version 1
-            return kActionStartSingleNodeElection;
-        }
         return kActionNone;
     }
 
@@ -3890,13 +3884,10 @@ ReplicationCoordinatorImpl::_updateMemberStateFromTopologyCoordinator(WithLock l
         _readWriteAbility->setCanServeNonLocalReads_UNSAFE(1U);
     }
 
-    if (newState.secondary() && _topCoord->getRole() == TopologyCoordinator::Role::kCandidate) {
-        // When transitioning to SECONDARY, the only way for _topCoord to report the candidate
-        // role is if the configuration represents a single-node replica set.  In that case, the
-        // overriding requirement is to elect this singleton node primary.
-        invariant(_rsConfig.getNumMembers() == 1 && _selfIndex == 0 &&
-                  _rsConfig.getMemberAt(0).isElectable());
-        // Start election in protocol version 1
+    if (newState.secondary() && result != kActionSteppedDown &&
+        _topCoord->isElectableNodeInSingleNodeReplicaSet()) {
+        // When transitioning from other follower states to SECONDARY, run for election on a
+        // single-node replica set.
         result = kActionStartSingleNodeElection;
     }
 
@@ -3982,9 +3973,7 @@ void ReplicationCoordinatorImpl::_performPostMemberStateUpdateAction(
             _externalState->stopAsyncUpdatesOfAndClearOplogTruncateAfterPoint();
             break;
         case kActionStartSingleNodeElection:
-            // In protocol version 1, single node replset will run an election instead of
-            // kActionWinElection as in protocol version 0.
-            _startElectSelfV1(StartElectionReasonEnum::kElectionTimeout);
+            _startElectSelfIfEligibleV1(StartElectionReasonEnum::kElectionTimeout);
             break;
         default:
             LOGV2_FATAL(26010,
@@ -4338,7 +4327,13 @@ ReplicationCoordinatorImpl::_setCurrentRSConfig(WithLock lk,
     _cancelPriorityTakeover_inlock();
     _cancelAndRescheduleElectionTimeout_inlock();
 
-    const PostMemberStateUpdateAction action = _updateMemberStateFromTopologyCoordinator(lk);
+    PostMemberStateUpdateAction action = _updateMemberStateFromTopologyCoordinator(lk);
+    if (_topCoord->isElectableNodeInSingleNodeReplicaSet()) {
+        // If the new config describes an electable one-node replica set, we need to start an
+        // election.
+        action = PostMemberStateUpdateAction::kActionStartSingleNodeElection;
+    }
+
     if (_selfIndex >= 0) {
         // Don't send heartbeats if we're not in the config, if we get re-added one of the
         // nodes in the set will contact us.
diff --git a/src/mongo/db/repl/replication_coordinator_impl.h b/src/mongo/db/repl/replication_coordinator_impl.h
index ac5d76919bd..392d8bd31f6 100644
--- a/src/mongo/db/repl/replication_coordinator_impl.h
+++ b/src/mongo/db/repl/replication_coordinator_impl.h
@@ -450,13 +450,13 @@ public:
         long long term, TopologyCoordinator::UpdateTermResult* updateResult);
 
     /**
-     * If called after _startElectSelfV1(), blocks until all asynchronous
+     * If called after _startElectSelfV1_inlock(), blocks until all asynchronous
      * activities associated with election complete.
      */
     void waitForElectionFinish_forTest();
 
     /**
-     * If called after _startElectSelfV1(), blocks until all asynchronous
+     * If called after _startElectSelfV1_inlock(), blocks until all asynchronous
      * activities associated with election dry run complete, including writing
      * last vote and scheduling the real election.
      */
@@ -1069,7 +1069,7 @@ private:
      * For proper concurrency, start methods must be called while holding _mutex.
      *
      * For V1 (raft) style elections the election path is:
-     *      _startElectSelfV1() or _startElectSelfV1_inlock()
+     *      _startElectSelfIfEligibleV1()
      *      _processDryRunResult() (may skip)
      *      _startRealElection_inlock()
      *      _writeLastVoteForMyElection()
@@ -1077,7 +1077,6 @@ private:
      *      _onVoteRequestComplete()
      */
     void _startElectSelfV1_inlock(StartElectionReasonEnum reason);
-    void _startElectSelfV1(StartElectionReasonEnum reason);
 
     /**
      * Callback called when the dryRun VoteRequester has completed; checks the results and
diff --git a/src/mongo/db/repl/replication_coordinator_impl_elect_v1.cpp b/src/mongo/db/repl/replication_coordinator_impl_elect_v1.cpp
index 849d83e4084..671563ea058 100644
--- a/src/mongo/db/repl/replication_coordinator_impl_elect_v1.cpp
+++ b/src/mongo/db/repl/replication_coordinator_impl_elect_v1.cpp
@@ -91,11 +91,6 @@ public:
     }
 };
 
-void ReplicationCoordinatorImpl::_startElectSelfV1(StartElectionReasonEnum reason) {
-    stdx::lock_guard<Latch> lk(_mutex);
-    _startElectSelfV1_inlock(reason);
-}
-
 void ReplicationCoordinatorImpl::_startElectSelfV1_inlock(StartElectionReasonEnum reason) {
     invariant(!_voteRequester);
 
diff --git a/src/mongo/db/repl/replication_coordinator_impl_elect_v1_test.cpp b/src/mongo/db/repl/replication_coordinator_impl_elect_v1_test.cpp
index ef8a7332b66..038c2568290 100644
--- a/src/mongo/db/repl/replication_coordinator_impl_elect_v1_test.cpp
+++ b/src/mongo/db/repl/replication_coordinator_impl_elect_v1_test.cpp
@@ -160,7 +160,7 @@ TEST_F(ReplCoordTest, ElectionSucceedsWhenNodeIsTheOnlyElectableNode) {
     }
     net->exitNetwork();
 
-    // _startElectSelfV1 is called when election timeout expires, so election
+    // _startElectSelfV1_inlock is called when election timeout expires, so election
     // finished event has been set.
     getReplCoord()->waitForElectionFinish_forTest();
 
@@ -904,6 +904,47 @@ TEST_F(ReplCoordTest, ElectionFailsWhenTermChangesDuringActualElection) {
         countTextFormatLogLinesContaining("Not becoming primary, we have been superseded already"));
 }
 
+TEST_F(ReplCoordTest, StartElectionOnSingleNodeInitiate) {
+    init("mySet");
+    start(HostAndPort("node1", 12345));
+    auto opCtx = makeOperationContext();
+    BSONObj configObj = configWithMembers(1, 0, BSON_ARRAY(member(1, "node1:12345")));
+
+    // Initialize my last applied, so that the node is electable.
+    replCoordSetMyLastAppliedAndDurableOpTime({Timestamp(100, 1), 0});
+
+    BSONObjBuilder result;
+    ASSERT_OK(getReplCoord()->processReplSetInitiate(opCtx.get(), configObj, &result));
+    ASSERT_EQUALS(MemberState::RS_RECOVERING, getReplCoord()->getMemberState().s);
+    // Oplog applier attempts to transition the state to Secondary, which triggers
+    // election on single node.
+    getReplCoord()->finishRecoveryIfEligible(opCtx.get());
+    // Run pending election operations on executor.
+    getNet()->enterNetwork();
+    getNet()->runReadyNetworkOperations();
+    getNet()->exitNetwork();
+    ASSERT_EQUALS(MemberState::RS_PRIMARY, getReplCoord()->getMemberState().s);
+}
+
+TEST_F(ReplCoordTest, StartElectionOnSingleNodeStartup) {
+    BSONObj configObj = configWithMembers(1, 0, BSON_ARRAY(member(1, "node1:12345")));
+    assertStartSuccess(configObj, HostAndPort("node1", 12345));
+
+    // Initialize my last applied, so that the node is electable.
+    replCoordSetMyLastAppliedAndDurableOpTime({Timestamp(100, 1), 0});
+
+    ASSERT_OK(getReplCoord()->setFollowerMode(MemberState::RS_RECOVERING));
+    // Oplog applier attempts to transition the state to Secondary, which triggers
+    // election on single node.
+    auto opCtx = makeOperationContext();
+    getReplCoord()->finishRecoveryIfEligible(opCtx.get());
+    // Run pending election operations on executor.
+    getNet()->enterNetwork();
+    getNet()->runReadyNetworkOperations();
+    getNet()->exitNetwork();
+    ASSERT_EQUALS(MemberState::RS_PRIMARY, getReplCoord()->getMemberState().s);
+}
+
 class TakeoverTest : public ReplCoordTest {
 public:
     /*
diff --git a/src/mongo/db/repl/replication_coordinator_impl_heartbeat.cpp b/src/mongo/db/repl/replication_coordinator_impl_heartbeat.cpp
index 0a9fd580a06..5521ded0cf8 100644
--- a/src/mongo/db/repl/replication_coordinator_impl_heartbeat.cpp
+++ b/src/mongo/db/repl/replication_coordinator_impl_heartbeat.cpp
@@ -1000,7 +1000,9 @@ void ReplicationCoordinatorImpl::_startElectSelfIfEligibleV1(WithLock,
                                                              StartElectionReasonEnum reason) {
     // If it is not a single node replica set, no need to start an election after stepdown timeout.
     if (reason == StartElectionReasonEnum::kSingleNodePromptElection &&
-        _rsConfig.getNumMembers() != 1) {
+        !_topCoord->isElectableNodeInSingleNodeReplicaSet()) {
+        LOGV2_FOR_ELECTION(
+            4764800, 0, "Not starting an election, since we are not an electable single node");
         return;
     }
 
diff --git a/src/mongo/db/repl/replication_coordinator_impl_reconfig_test.cpp b/src/mongo/db/repl/replication_coordinator_impl_reconfig_test.cpp
index 0e7fee0157f..b110f93b5f6 100644
--- a/src/mongo/db/repl/replication_coordinator_impl_reconfig_test.cpp
+++ b/src/mongo/db/repl/replication_coordinator_impl_reconfig_test.cpp
@@ -779,17 +779,6 @@ public:
     unittest::MinimumLoggedSeverityGuard severityGuard{logv2::LogComponent::kDefault,
                                                        logv2::LogSeverity::Debug(3)};
 
-    BSONObj member(int id, std::string host) {
-        return BSON("_id" << id << "host" << host);
-    }
-
-    BSONObj configWithMembers(int version, long long term, BSONArray members) {
-        return BSON("_id"
-                    << "mySet"
-                    << "protocolVersion" << 1 << "version" << version << "term" << term << "members"
-                    << members);
-    }
-
     void respondToHeartbeat() {
         auto net = getNet();
         auto noi = net->getNextReadyRequest();
@@ -1386,6 +1375,34 @@ TEST_F(ReplCoordReconfigTest, StepdownShouldInterruptConfigWrite) {
     ASSERT_EQ(status.reason(), "Stepped down when persisting new config");
 }
 
+TEST_F(ReplCoordReconfigTest, StartElectionOnReconfigToSingleNode) {
+    // Start up as a secondary.
+    init();
+    assertStartSuccess(
+        configWithMembers(
+            1, 0, BSON_ARRAY(member(1, "n1:1") << member(2, "n2:1") << member(3, "n3:1"))),
+        HostAndPort("n1", 1));
+    ASSERT_OK(getReplCoord()->setFollowerMode(MemberState::RS_SECONDARY));
+
+    // Simulate application of one oplog entry.
+    replCoordSetMyLastAppliedAndDurableOpTime(OpTime(Timestamp(1, 1), 0));
+
+    // Construct the new config of single node replset.
+    auto configVersion = 2;
+    ReplSetReconfigArgs args;
+    args.force = true;
+    args.newConfigObj = configWithMembers(configVersion, 1, BSON_ARRAY(member(1, "n1:1")));
+
+    BSONObjBuilder result;
+    const auto opCtx = makeOperationContext();
+    ASSERT_OK(getReplCoord()->processReplSetReconfig(opCtx.get(), args, &result));
+    getNet()->enterNetwork();
+    getNet()->runReadyNetworkOperations();
+    getNet()->exitNetwork();
+
+    ASSERT_EQUALS(MemberState::RS_PRIMARY, getReplCoord()->getMemberState().s);
+}
+
 }  // anonymous namespace
 }  // namespace repl
 }  // namespace mongo
diff --git a/src/mongo/db/repl/replication_coordinator_test_fixture.h b/src/mongo/db/repl/replication_coordinator_test_fixture.h
index cef52cd81e9..e74e89bc6ee 100644
--- a/src/mongo/db/repl/replication_coordinator_test_fixture.h
+++ b/src/mongo/db/repl/replication_coordinator_test_fixture.h
@@ -76,6 +76,20 @@ public:
      */
     static BSONObj addProtocolVersion(const BSONObj& configDoc, int protocolVersion);
 
+    /**
+     * Helpers to construct a config.
+     */
+    static BSONObj member(int id, std::string host) {
+        return BSON("_id" << id << "host" << host);
+    }
+
+    static BSONObj configWithMembers(int version, long long term, BSONArray members) {
+        return BSON("_id"
+                    << "mySet"
+                    << "protocolVersion" << 1 << "version" << version << "term" << term << "members"
+                    << members);
+    }
+
 protected:
     ReplCoordTest();
     virtual ~ReplCoordTest();
diff --git a/src/mongo/db/repl/topology_coordinator.cpp b/src/mongo/db/repl/topology_coordinator.cpp
index 96f02005bfb..ad7373215da 100644
--- a/src/mongo/db/repl/topology_coordinator.cpp
+++ b/src/mongo/db/repl/topology_coordinator.cpp
@@ -2196,13 +2196,6 @@ void TopologyCoordinator::updateConfig(const ReplSetConfig& newConfig, int selfI
 
     // By this point we know we are in Role::kFollower
     _currentPrimaryIndex = -1;  // force secondaries to re-detect who the primary is
-
-    if (_isElectableNodeInSingleNodeReplicaSet()) {
-        // If the new config describes a one-node replica set, we're the one member,
-        // we're electable, we're not in maintenance mode and we are currently in followerMode
-        // SECONDARY, we must transition to candidate, in leiu of heartbeats.
-        _role = Role::kCandidate;
-    }
 }
 std::string TopologyCoordinator::_getHbmsg(Date_t now) const {
     // ignore messages over 2 minutes old
@@ -2646,24 +2639,13 @@ void TopologyCoordinator::setFollowerMode(MemberState::MS newMode) {
         default:
             MONGO_UNREACHABLE;
     }
-
-    if (_followerMode != MemberState::RS_SECONDARY) {
-        return;
-    }
-
-    // When a single node replica set transitions to SECONDARY, we must check if we should
-    // be a candidate here.  This is necessary because a single node replica set has no
-    // heartbeats that would normally change the role to candidate.
-
-    if (_isElectableNodeInSingleNodeReplicaSet()) {
-        _role = Role::kCandidate;
-    }
 }
 
-bool TopologyCoordinator::_isElectableNodeInSingleNodeReplicaSet() const {
-    return _followerMode == MemberState::RS_SECONDARY && _rsConfig.getNumMembers() == 1 &&
-        _selfIndex == 0 && _rsConfig.getMemberAt(_selfIndex).isElectable() &&
-        _maintenanceModeCalls == 0;
+bool TopologyCoordinator::isElectableNodeInSingleNodeReplicaSet() const {
+    auto isSingleNode = _rsConfig.getNumMembers() == 1 && _selfIndex == 0;
+    // Single node replset must be electable.
+    invariant(!isSingleNode || _rsConfig.getMemberAt(_selfIndex).isElectable());
+    return (getMemberState() == MemberState::RS_SECONDARY) && isSingleNode;
 }
 
 void TopologyCoordinator::finishUnconditionalStepDown() {
diff --git a/src/mongo/db/repl/topology_coordinator.h b/src/mongo/db/repl/topology_coordinator.h
index 0e9f90aef21..752b9b52b2f 100644
--- a/src/mongo/db/repl/topology_coordinator.h
+++ b/src/mongo/db/repl/topology_coordinator.h
@@ -171,6 +171,16 @@ public:
 
     enum class UpdateTermResult { kAlreadyUpToDate, kTriggerStepDown, kUpdatedTerm };
 
+    /**
+     * Returns true if we are a one-node replica set, we're the one member,
+     * we're electable, we're not in maintenance mode, and we are currently in followerMode
+     * SECONDARY.
+     *
+     * This is used to decide if we should start an election in a one-node replica set.
+     */
+    bool isElectableNodeInSingleNodeReplicaSet() const;
+
+
     ////////////////////////////////////////////////////////////
     //
     // Basic state manipulation methods.
@@ -945,15 +955,6 @@ private:
      **/
     bool _memberIsBlacklisted(const MemberConfig& memberConfig, Date_t now) const;
 
-    /**
-     * Returns true if we are a one-node replica set, we're the one member,
-     * we're electable, we're not in maintenance mode, and we are currently in followerMode
-     * SECONDARY.
-     *
-     * This is used to decide if we should transition to Role::candidate in a one-node replica set.
-     */
-    bool _isElectableNodeInSingleNodeReplicaSet() const;
-
     // Returns a string representation of the current replica set status for logging purposes.
     std::string _getReplSetStatusString();
 
diff --git a/src/mongo/db/repl/topology_coordinator_v1_test.cpp b/src/mongo/db/repl/topology_coordinator_v1_test.cpp
index 2ef75f15402..96b9f3a9cda 100644
--- a/src/mongo/db/repl/topology_coordinator_v1_test.cpp
+++ b/src/mongo/db/repl/topology_coordinator_v1_test.cpp
@@ -2893,24 +2893,6 @@ TEST_F(TopoCoordTest, RespondToHeartbeatsWithNullLastAppliedAndLastDurableWhileI
     ASSERT_EQUALS(OpTime(), response.getDurableOpTime());
 }
 
-TEST_F(TopoCoordTest, BecomeCandidateWhenBecomingSecondaryInSingleNodeSet) {
-    ASSERT_TRUE(TopologyCoordinator::Role::kFollower == getTopoCoord().getRole());
-    ASSERT_EQUALS(MemberState::RS_STARTUP, getTopoCoord().getMemberState().s);
-    updateConfig(BSON("_id"
-                      << "rs0"
-                      << "version" << 1 << "members"
-                      << BSON_ARRAY(BSON("_id" << 1 << "host"
-                                               << "hself"))),
-                 0);
-    ASSERT_EQUALS(MemberState::RS_STARTUP2, getTopoCoord().getMemberState().s);
-
-    // if we are the only node, we should become a candidate when we transition to SECONDARY
-    ASSERT_FALSE(TopologyCoordinator::Role::kCandidate == getTopoCoord().getRole());
-    getTopoCoord().setFollowerMode(MemberState::RS_SECONDARY);
-    ASSERT_TRUE(TopologyCoordinator::Role::kCandidate == getTopoCoord().getRole());
-    ASSERT_EQUALS(MemberState::RS_SECONDARY, getTopoCoord().getMemberState().s);
-}
-
 TEST_F(TopoCoordTest, DoNotBecomeCandidateWhenBecomingSecondaryInSingleNodeSetIfInMaintenanceMode) {
     ASSERT_TRUE(TopologyCoordinator::Role::kFollower == getTopoCoord().getRole());
     ASSERT_EQUALS(MemberState::RS_STARTUP, getTopoCoord().getMemberState().s);
@@ -2938,36 +2920,6 @@ TEST_F(TopoCoordTest, DoNotBecomeCandidateWhenBecomingSecondaryInSingleNodeSetIf
     ASSERT_EQUALS(MemberState::RS_SECONDARY, getTopoCoord().getMemberState().s);
 }
 
-TEST_F(TopoCoordTest, BecomeCandidateWhenReconfigToBeElectableInSingleNodeSet) {
-    ASSERT_TRUE(TopologyCoordinator::Role::kFollower == getTopoCoord().getRole());
-    ASSERT_EQUALS(MemberState::RS_STARTUP, getTopoCoord().getMemberState().s);
-    ReplSetConfig cfg;
-    cfg.initialize(BSON("_id"
-                        << "rs0"
-                        << "version" << 1 << "protocolVersion" << 1 << "members"
-                        << BSON_ARRAY(BSON("_id" << 1 << "host"
-                                                 << "hself"
-                                                 << "priority" << 0))))
-        .transitional_ignore();
-    getTopoCoord().updateConfig(cfg, 0, now()++);
-    ASSERT_EQUALS(MemberState::RS_STARTUP2, getTopoCoord().getMemberState().s);
-
-    ASSERT_FALSE(TopologyCoordinator::Role::kCandidate == getTopoCoord().getRole());
-    getTopoCoord().setFollowerMode(MemberState::RS_SECONDARY);
-    ASSERT_FALSE(TopologyCoordinator::Role::kCandidate == getTopoCoord().getRole());
-    ASSERT_EQUALS(MemberState::RS_SECONDARY, getTopoCoord().getMemberState().s);
-
-    // we should become a candidate when we reconfig to become electable
-
-    updateConfig(BSON("_id"
-                      << "rs0"
-                      << "version" << 1 << "members"
-                      << BSON_ARRAY(BSON("_id" << 1 << "host"
-                                               << "hself"))),
-                 0);
-    ASSERT_TRUE(TopologyCoordinator::Role::kCandidate == getTopoCoord().getRole());
-}
-
 TEST_F(TopoCoordTest,
        DoNotBecomeCandidateWhenReconfigToBeElectableInSingleNodeSetIfInMaintenanceMode) {
     ASSERT_TRUE(TopologyCoordinator::Role::kFollower == getTopoCoord().getRole());
@@ -3095,7 +3047,9 @@ TEST_F(TopoCoordTest, NodeTransitionsToRemovedWhenRemovedFromConfigEvenWhenPrima
     ASSERT_FALSE(TopologyCoordinator::Role::kCandidate == getTopoCoord().getRole());
     ASSERT_EQUALS(MemberState::RS_STARTUP2, getTopoCoord().getMemberState().s);
     getTopoCoord().setFollowerMode(MemberState::RS_SECONDARY);
-    ASSERT_TRUE(TopologyCoordinator::Role::kCandidate == getTopoCoord().getRole());
+    setMyOpTime({Timestamp(1, 1), 0});
+    ASSERT_OK(getTopoCoord().becomeCandidateIfElectable(Date_t(),
+                                                        StartElectionReasonEnum::kElectionTimeout));
 
     // win election and primary
     getTopoCoord().processWinElection(OID::gen(), Timestamp());
@@ -3128,7 +3082,9 @@ TEST_F(TopoCoordTest, NodeTransitionsToSecondaryWhenReconfiggingToBeUnelectable)
     ASSERT_FALSE(TopologyCoordinator::Role::kCandidate == getTopoCoord().getRole());
     ASSERT_EQUALS(MemberState::RS_STARTUP2, getTopoCoord().getMemberState().s);
     getTopoCoord().setFollowerMode(MemberState::RS_SECONDARY);
-    ASSERT_TRUE(TopologyCoordinator::Role::kCandidate == getTopoCoord().getRole());
+    setMyOpTime({Timestamp(1, 1), 0});
+    ASSERT_OK(getTopoCoord().becomeCandidateIfElectable(Date_t(),
+                                                        StartElectionReasonEnum::kElectionTimeout));
 
     // win election and primary
     getTopoCoord().processWinElection(OID::gen(), Timestamp());
@@ -3164,7 +3120,9 @@ TEST_F(TopoCoordTest, NodeMaintainsPrimaryStateAcrossReconfigIfNodeRemainsElecta
     ASSERT_FALSE(TopologyCoordinator::Role::kCandidate == getTopoCoord().getRole());
     ASSERT_EQUALS(MemberState::RS_STARTUP2, getTopoCoord().getMemberState().s);
     getTopoCoord().setFollowerMode(MemberState::RS_SECONDARY);
-    ASSERT_TRUE(TopologyCoordinator::Role::kCandidate == getTopoCoord().getRole());
+    setMyOpTime({Timestamp(1, 1), 0});
+    ASSERT_OK(getTopoCoord().becomeCandidateIfElectable(Date_t(),
+                                                        StartElectionReasonEnum::kElectionTimeout));
 
     // win election and primary
     getTopoCoord().processWinElection(OID::gen(), Timestamp());